Re: Spm used but plan is different

Hi Kunwar,

I believe the signature matching won’t be an issue if you’re taking it from a packed baseline table (the import process fixed the signature issue).

I would focus on the optimizer trace for now.

Andy

On Wed, 22 May 2019 at 20:27, kunwar singh <krishsingh.111_at_gmail.com> wrote:

> Hi Andy, . Yes I am creating the baseline and then importing to 12.2 . I
> will check on the signature . I am not the dba with all the access :(, so
> it will be a day before I can confirm
>
> On Wed, May 22, 2019 at 2:18 PM Andy Sayer <andysayer_at_gmail.com> wrote:
>
>> Hi Kunwar,
>>
>> When you say you’re copying the plan from 11g, does this mean you’re
>> creating a baseline table and exporting/importing it to the 12.2 DB? Or are
>> you gathering the baseline before you upgrade?
>>
>> Does the SQL still have the same exact_matching_signature?
>> If so, the optimizer trace will help you out.
>>
>> Typically the plan in the baseline is no longer legal - perhaps it was
>> relying on a transformation that has been removed as part of a bug fix,
>> perhaps the indexes have changed.
>>
>> Hope that helps,
>> Andy
>>
>> On Wed, 22 May 2019 at 18:23, kunwar singh <krishsingh.111_at_gmail.com>
>> wrote:
>>
>>> hi listers
>>> We are migrating from 11g to 12.2
>>> And as part of performance testing we found that few plans regressed and
>>> I tried to copy the plan from 11g using spm .
>>> Spm is getting used but plans are different and run times are bad still.
>>> Same is the case by using ofe of 11.2.0.4 .
>>> Don’t see any helpful notes on mos for the steps I should take to
>>> resolve why plans are not same . And there is no single common difference
>>> in the plans which is causing this issue .
>>>
>>> So wanted to know what your methodology in finding why spm is not using
>>> the same plan . Same is the case with sql profile and it getting used
>>>
>>> my question is more in general and not query specific .
>>>
>>>
>>> --
>>> Cheers,
>>> Kunwar
>>>
>> --
> Cheers,
> Kunwar
>

--
http://www.freelists.org/webpage/oracle-l